1973时间题，最后一句便是答案所在。

Henry Alfred Kissinger was born in Germany of Jewish nationality on May 27, 1923. He came to the United States in 1938 and became a U.S. citizen in 1943. He served in the U.S. Army in World War Ⅱ from 1943～1946. He studied political science at Harvard University and got his doctoral degree there. He also taught there from 1954 until 1969. He was a unique teacher and admired by his students.
     Dr. Kissinger entered government service in 1969 and eventually became the most celebrated American Secretary of State since Thomas Jefferson. He was chief foreign policy advisor and Secretary of State to Presidents Richard Nixon and Gerald Ford. Among Kissinger’s achievements were the restoration of U. S. relations with the People’s Republic of China and the arrangement—by "shuttle diplomacy"—of a cease-fire between the Israelis and the Arabs in the Arab Israeli War of 1973. He also negotiated a cease-fire in Vietnam and was awarded Nobel Peace Prize for 1973 for his role in U.S. troops withdrawing from Vietnam.